Spot sign characteristics
| CTA Spot Positive (n = 8) | CTP Spot Positive (n = 14) | PCT Spot Positive (n = 9) | P Valuea | |
|---|---|---|---|---|
| Spot No. | 2 (1–4) | 3 (1–6) | 2 (1–2) | .178 |
| Maximum attenuation (HU) | 252 (195–285) | 219 (155–308) | 140 (130–46) | .011 |
| Maximum axial dimension (mm) | 4.6 (2.5–6.6) | 9.1 (4.7–20.1) | 19.0 (11.0–21.3) | .055 |
| Spot sign score | 3 (2–3) | 3.5 (1–4) | 2 (2–3) | .125 |
| Time from contrast injection to maximum attenuation (sec) | 24 (22–26) | 50 (34–63) | 339 (308–370) | <.001 |
↵a Overall difference among groups determined by Kruskal-Wallis test.